Installation assist mechanism for busway plugs



Jan. 13, 1970 Q gmcsofl ETAL 3,489,983

INSTALLATION ASSIST MECHANISM FOR BUSWAY PLUGS Filed Sept. 14, 1967 5 Sheets-Sheet 1 /N VN TORS Ema A. Emcsou, FREDERICK D. /(A UFHOLD A TTOR/VEY Jan. 13, 1970 ERlcsON ET AL 3,489,983

INSTALLATION ASSIST MECHANISM FOR BUSWAY PLUGS Filed Sept. 14, 196'? 5 Sheets-Sheet 2 FIG.3

/N VENTURE ER/c A. Ei e/(501v, FKEDERICK Q /(A un/aw ATTORNEY E. A. ERICSON E AL I INSTALLATION ASSIST MECHANISM FOR BUSWAY PLUGS Filed Sept. 14, 1967 Jan. 13, 1970 3 Sheets-Sheet 3 s a Z NR W A m R E ICTH-IDERKK Q /(A ammo BY was, 5 in; an

A TTDRNEV United States Patent O 3,489,983 INSTALLATION ASSIST MECHANISM FOR BUSWAY PLUGS Eric A. Ericson, Plainville, and Frederick D. Kaufhold,

Forestville, Conn., assignors to General Electric Company, a corporation of New York Filed Sept. 14, 1967, Ser. No. 667,777 Int. Cl. H011 13/60 US. Cl. 33922 8 Claims ABSTRACT OF THE DISCLOSURE A busway plug having at each end an elongated member carrying two busway-engaging hook members at its ends; and at one end, a mechanism including a toggle link arrangement is provided which operates a movable slide to which one of the elongated members is attached; the slide is operated by means of a nut, rotation of which causes relative motion between the slide and the plug body to move the plug stabs relative to the busbars.

BACKGROUND OF THE INVENTION Field of the invention Our invention relates to plug-in type power take-off devices for use with busbar type electric power distribution systems commonly referred to as busways, and more particularly to such devices which include means for facilitating the installation thereof on busways.

Description of the prior art The installation of power take-off plugs on an overheadmounted busway usually requires that the person doing the installing perch himself on a stepladder, etc. in order to reach the busway in its elevated location. One difficulty encountered in the mounting of such overhead power take-off busway plugs which has become increasingly troublesome as busway plugs have become larger both in physical size and in current carrying capacity relates to the engagement and disengagement of the stab fingers of the plug with the busbars of the busway. It takes a significant amount of force to open the stab fingers and slide them onto the busbars. Providing the amount of force required for this purpose while perched on a stepladder and while trying to mount the plug to the busway has been and remains a problem notwithstanding the various attempts that have been made to alleviate the difficulty.

OBJECTS OF THE INVENTION It is an object of the present invention to provide a busway plug having means which enables the plug to be readily and easily installed on an electric power busway.

It is a further object of the present invention to provide a busway plug having force-multiplying means for forcing the connectors of the plug onto the busbars of the busway after the plug has been physically connected to the busway.

It is another object of the present invention to provide such a means which may be utilized with presently existing busway plugs without requiring substantial modification of the plug or increase in the cost of manufacture thereof.

A still further object of the present invention is to provide a busway plug having such means which may be installed on presently existing busways without requiring any modifications in the busway.

Still another object of the present invention is to provide a busway plug having such means which facilitates the mechanical attachment of the plug to the busway as 3,489,983 Patented Jan. 13, 1970 ICC SUMMARY OF THE INVENTION In accordance with the present invention there is provided a plug-in type electric power take-off device comprising a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent a busway housing. A plurality of plug-in type electrical connectors are supported on the bottom wall of the rectangular enclosure and project externally therefrom for engagement with the busbars supported in the busway housing. A clamping bracket which is mounted on the bottom wall of the rectangular enclosure adjacent one end thereof has a pair of inwardly directed portions for engaging external surface portions of the busway hous ing to attach said one end of the device to the busway housing. Mounted in juxtaposed relation to the bottom wall of the rectangular enclosure adjacent the other end thereof is a support means which includes means for attaching the latter end of the device to the busway housing. The support means is movable between a first position wherein with the power take-01f device attached to the busway housing the plug-in electrical connectors are out of contact with the busbars supported in the busway housing and a second position wherein the plug-in electrical connectors engage the busbars in the busway housing.

The invention will be more fully understood from the following detailed description and its scope will be pointed out in the appended claims.

BRIEF DESCRIPTION OF THE DRAWING In the drawings,

FIGURE 1 is an end view of a busway plug incorporating the present invention, shown mounted on a busway with the plug stabs in engagement with the busbars of the busway;

FIGURE 2. is a partially exploded perspective view of the busway plug of FIGURE 1;

FIGURE 3 is a side view of a busway plug incorporating the present invention, shown mounted on a section of busway with the plug stabs disengaged from the busbars of the busway;

FIGURE 4 is a side view similar to FIGURE 3 of a busway plug mounted on a section of busway illustrating the plug stabs in engagement with the busbars of the busy;

FIGURE 5 is a sectional view of the movably mounted clamping member of the busway plug of FIGURE 4;

FIGURE 6 is a sectional view of the fixedly mounted clamping member of the busway plug of FIGURE 4;

FIGURE 7 is a partially exploded perspective view of the slide mechanism of the busway plug of FIGURE 1, illustrated in the retracted position; and

FIGURE 8 is a perspective view of the slide mechanism similar to FIGURE 7, illustrating the slide mechanism in the extended position.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring now to the drawings, the invention is shown as incorporated in a busway power take-off plug device 10, shown mounted on an electric busway 11. The plug device 10 includes a generally rectangular outer metallic enclosure which is generally box-like in construction and includes a bottom wall 12, side walls 13 and 14, end walls 3 and 16, and an open top wall closed by a cover 17. As shown in FIGURE 1, the cover 17 is held in that position by means of a spring-biased hook member 18 mounted on the side wall of the enclosure and passing through an opening (not shown) in the cover.

Protruding through an opening 12a in the bottom wall 12 of the plug device 10 are a plurality of plug-in type contacts 19 which are mounted on the insulating support 20, the latter being secured by suitable means on the inner surface of the bottom wall 12. The plug-in contacts 19 as is well-known in the art are connected by suitable connecting straps (not shown) to electrical switching means (not shown) housed in the plug device 10. For the purpose of guiding the plug device 10 into properly aligned engagement with the busway 11, a pair of combined guide and barrier members 21 and 22 are also provided, mounted on the insulating support 20. If desired, one of the guide members, such as guide member 22 as illustrated in FIGURE 2, can be slidably mounted on the support and suitably coupled to the operating mechanism enclosed in the plug device 10 for providing an interlocking action in accordance with the teachings of U.S. Patent 2,984,769 issued May 16, 1961 to C. B. Turton, and assigned to the same assignee as the present invention.

Referring now particularly to FIGURES 1, 3, and 4, the power take-off plug device 10 is shown as adapted for use with a power busway 11 comprising an elongated generally rectangular metallic housing including side walls 23 and 24 and top and bottom walls 25 and 26 respectively, jointed together by suitable means such as by screws (not shown) through overlapping edge portions thereof. The busway 11 includes a plurality of electric power busbar conductors 27 supported in insulated relation therein by longitudinally spaced insulating suports (not shown). The bottom wall 26 of the busway is provided with one or more openings 26a per given length of a section of busway to permit the entry of the power take-off contacts 19 for engagement with the busbar conductors 27.

For the purpose of supporting the power take-off plug device 10 on the busway housing, the plug device 10 includes a pair of channel members 28 and 29, to each of which are resiliently attached a pair of busyway-engaging hook members 30 and 31, respectively, such as by Springbiasing means 32. The hook members 30 and 3.1 engage the flange portions 23a and 24a, respectively, of the busway side walls 23 and 24 when the plugs is mounted on the busway, as shown for example in FIGURE 1.

As may be seen by reference to FIGURE 6, the channel member 28 is mounted on the bottom wall 12 of the plug device 10 adjacent the side wall 16 thereof by means of a pair of screws 33 (only one shown) the ends of which extend outwardly through the bottom wall 12 and are received in suitable openings (not shown) in the web portion of the channel member 28. Nuts 34 (only one of which is shown) secure the channel member 28 to the bolts 33. By virtue of the bumped portion 28a of the channel member 28, the channel member 28 is free to pivot slightly on the screws 33 to the position illustrated for example in dotted lines in FIGURE 6 and in solid lines in FIGURE 3 for a purpose to be described hereinafter in connection with the steps of mounting the plug device 10 on the busway 11.

Refering now to FIGURES 7 and 8, the central portion 15a of the end wall .15 of the plug device 10 is bumped outwardly sufliciently to provide space for housing the installation assist mechanism 35. The mechanism 35 comprises a disc 36 to which a pair of L-shaped links 37 are attached at one end thereof by suitable means such as by a stud 38. The other ends of the links 37 are attached similarly to a movable slide 39 by means of a stud 40. The slide 39 has a pair of elongated slots 41 therein, in each of which there is positioned a guide member 42 for guiding the rectilinear movement of the slide 39. The disc 36 is secured in place by means of the hexagonally shaped nut 43 and the screw 44 as best seen in FIGURE 7, the nut 43 passing through an opening suitably provided in the end wall 15. By virtue of the connection between the disc 36, the links 37, and the slide 39, the rotational movement of the disc 36, imparted thereto by rotation of the nut 43, is translated to rectilinear movement of the slide 39. The slide 39 may thereby be moved between a retracted position within the housing of the plug device 10 as illustrated in FIGURE 7, and the position illustrated in FIGURE 8 wherein the slide 39 is extended outwardly relative to the bottom wall of the plug device 10. Preferably the hexagonally-shaped nut 43 is provided with an indicator member 45 which is fixedly secured thereto. The rotational position of the nut 43 which in turn as noted above determines the position of the slide 39 may thus be determined by noting the position the pointer 45a of the indicator member 45 bears with relation to the IN and OUT legend carried by the end wall 15 as seen in FIGURES 1 and 2.

The previously described channel member 29 is mounted on the slide 39 for movement therewith by means of the inwardly extending foot portions 46 thereof which enter a pair of slots 29a suitably provided in the side of the web of the channel member 29 (see FIGURE 2). The portions 46 are retained in the slots 29a by means of studs 47 which are received in the openings 48 provided therefor in the portions 46 and in suitable openings (not shown) in the web of the channel member 29. As shown in FIGURE 5, the slots 29a are dimensioned such as to permit the channel member 29 to pivot to a limited extent on the foot portions 46 of the slide 39 as seen in dotted lines therein.

In the preferred embodiment, the handle 49 which is normally utilized to operate the electrical mechanism housed in the plug device .10 is provided at one end thereof with a hexagonal opening 49a which corresponds to the shape and dimensions of the nut 43. Further the handle 49 is detachably mounted by suitable means on the plug device 10 whereby the handle 49 may be employed as a wrench to rotate the nut 43 by removing the handle from its mounted position and placing the hexagonal opening 49a thereof over the hexagonal head of the nut 43, and thereafter turning the nut.

To install the plug device 10 on the busway 11, the slide 39 is first moved to its extended position as shown in FIGURE 8 by rotating the nut 43 by means of the hande 49 until the pointer 45a of the indicator member 45 is adjacent the OUT legend found on the end wall 15. The busway-engaging hook members 30 of the channel-shaped member 28 are then attached to the flanges 23a and 24a of the side walls 23 and 24 of the busway 11. The hook members 31 of the channel member 29 are likewise attached to the flanges 23a and 24a. Thereafter, by using the handle 49 and giving the nut 43 a turn of approximately the slide 39 is retracted into the housing of the plug device 10 to the position shown in FIGURE 7. As the slide 39 is retracted, the plug-in contacts 19 are brought into contact with the busbar conductors 27 of the busway 11 by virtue of the movement of the bottom wall 12 of the plug device 10 relative to the bottom wall 26 of the busway 11. The engagement of the plug-in contacts 19 with the busbar conductors 27 can be easily accomplished during the movement of the slide 39 inasmuch as the mechanical advantage of the installation assist mechanism 35 can be in the neighborhood of 24 to 1 thus only requiring a reduced amount of force to be applied by the worker rotating the nut 43 with the handle 49.

While the invention has been illustrated in a specific embodiment utilizing a particular type of plug-in power take-oif device and busway, it is to be understood that the present invention may be employed with other types of power take-off devices and busways, and it is therefore intended by the appended claims to cover all such modifications as fall within the true spirit and scope of the invention.

What We claim as new and desire to secure by Letters Patent of the United States is:

1. An electric power take-off device for use with electric power busway having a housing containing busbars comprising:

(a) a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(c) a clamping bracket mounted on said rectangular enclosure adjacent one end thereof for pivotal movement relative thereto, said clamping bracket including a pair of hook-shaped portions for engaging external surface portions of said busway housing;

(d) support means mounted on said enclosure adjacent the other end thereof for attaching said other end of said enclosure to said busway housing; and

(e) moving means carried by said enclosure for moving said support means with respect to said enclosure whereby when said support means is attached to said busway housing, said moving means can be operated to cause relative movement between said support means and said enclosure and thereby to move said enclosure with respect to said busway and to move said plug-in type electrical connectors into engagement with said busbars.

2. An electric power take-off device for use with electric power busway having a housing containing busbars comprising:

(a) a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(c) a first mounting means mounted on said rectangular enclosure adjacent one end thereof, said first mounting means including a first pair of up-standing portions for engaging opposed portions of said busway housing, said first mounting means providing for pivotal movement of said enclosure about a transverse axis adjacent said one end thereof;

(d) a second mounting means mounted on said enclosure adjacent the other end thereof, said second mounting means including a U-shaped member having a bight portion extending transversely of said enclosure and a second pair of up-standing portions for engaging opposed portions of said busway housing to attach said other end of said enclosure to said busway housing; and

(e) moving means carried by said enclosure for moving said U-shaped member as a unit with respect to said enclosure whereby when said second pair of up-standing portions is attached to said busway housing, said moving means can be operated to move said enclosure and thereby said plug-in type electrical connectors into engagement with said busbar.

3. An electric power take-off device for use with electric power busway having a housing containing busbars comprising:

(a) a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(0) a first clamping means comprising a first formed channel member mounted on said rectangular enclosure adjacent one end thereof for pivotal movement relative thereto;

((1) a first pair of hook-shaped portions resiliently mounted on said first formed channel member for engaging external surface portions of said busway housing;

(e) a second clamping means comprising a second formed channel member and a second pair of hookshaped portions resiliently mounted on said second formed channel member for engaging external surfaces of said busway housing;

(f) means mounting said second clamping means on said enclosure, said mounting means including a slide member supported on said enclosure; and

(g) moving means carried by said enclosure for moving said slide member and thereby said second clamping means with respect to said enclosure whereby when said second clamping means is attached to said busway housing, said moving means can be operated to move said enclosure and thereby said plug-in type electrical connectors into engagement with said busbars.

4. An electric power take-off device as set forth in claim 3 wherein:

(a) said moving means includes a toggle link mechanism comprising a pair of link members each having one end thereof secured to said slide member, and a disc member mounted on said enclosure for rotational movement; and

(b) means securing the other ends 'of said link members to said disc member whereby rotational movement of said disc member is translated into rectilinear movement of said slide member.

5. An electric power take-01f device for use with electric power busway having a housing containing busbars comprising:

(a) a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in 'said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(c) a first clamping means comprising a first formed channel member mounted on said rectangular enclosure adjacent one end thereof for movement relative thereto;

(d) a first pair of hook-shaped portions resiliently mounted on said first formed channel member for engaging external surface portions of said busway housing;

(e) a second clamping means comprising a second formed channel member and a second pair of bookshaped portions resiliently mounted on said second formed channel member for engaging external surfaces of said busway housing;

(f) means mounting said second clamping means on said enclosure, said mounting means including a slide member supported on said enclosure;

(g) means for moving said slide member and thereby said second clamping means with respect to said enclosure whereby when said second clamping means is attached to said busway housing, said moving means can be operated to move said enclosure and thereby said plug-in type electrical connectors into engagement with said busbars;

(h) said moving means includes a toggle link mechanism comprising a pair of link members each having one end thereof secured to said slide member,

and a disc member mounted on said enclosure for rotational movement;

(i) means securing the other ends of said link members to said disc member whereby rotational movement of said disc member is translated into rectilinear movemnt of said slide member; and

(j) means detachably mounted on one of the exterior surfaces of said rectangular enclosure, said detachably mounted means being used to impart said rotational movement to said disc member.

6. An electric power take-off device as set forth in claim 4 wherein said device further comprises:

(a) indicator means for indicating the position of said second clamping means relative to said enclosure; and

(b) means mounting said indicator means on said disc member for rotation therewith.

7. An electric power take-off device for use with electrict power busway having a housing containing busbars comprising:

(a) a generally rectangular enclosure having a top wall, side walls, and a bottom wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(c) a clamping means comprising a formed channel member and a pair of hook-shaped portions resiliently mounted on said formed channel member for engaging external surfaces of said busway housing;

(d) mean-s mounting said clamping means on said enclosure, said mounting means including a slide member supported on said enclosure;

(e) means for moving said slide member and thereby said clamping means with respect to said enclosure whereby When said clamping means is attached to said busway housing, said moving means can be operated to move said enclosure and thereby said plug-in type electrical connectors into en-' gagement with said busbars;

(f) said moving means including a toggle link mechanism comprising at least one link member having one end thereof secured to said slide member, and a disc member mounted on said enclosure for ro-' tational movement;

(g) means securing the other end of said link member to said disc member whereby rotational movement of said disc member is translated into rectilinear movement of said slide member;

(h) said clamping means being positioned adjacent one end of said enclosure; and

(i) second mounting means carried by said enclosure adjacent the other end thereof, said second mounting means providing for pivotal movement of said enclosure about transverse axis adjacent said other end upon movement of said enclosure by said moving means.

8. An electric power take-off device for use with electric power busway having a housing containing busbars comprising:

(a). a generally rectangular enclosure having a top wall, side walls, and a bottom Wall for mounting adjacent said busway housing;

(b) a plurality of plug-in type electrical connectors supported in said rectangular enclosure, said connectors projecting externally from said bottom wall for engagement with said busbars in said busway housing;

(c) a clamping means comprising a formed channel member and a pair of hook-shaped portions resiliently mounted on said formed channel member for engaging external surfaces of said busway housing;

((1) means mounting said clamping means on said enclosure, said mounting means including a slide member supported on said enclosure;

(e) means for moving said slide member and thereby said clam-ping means with respect to said enclosure whereby when said clamping means is attached to said busway housing, said moving means can be operated to move said enclosure and thereby said plug-in type electrical connectors into engagement with said busbars;

(f) said moving means including a toggle link mechanism comprising a pair of link members each having one end thereof secured to said slide member, and a disc member mounted on said enclosure for rotational movement;

(g) means securing the other ends of said link members to said disc member whereby rotationalmovement of said disc member is translated into rectilinear movement of said slide member; and

(h) means detachably mounted on one of the exterior surfaces of said rectangular enclosure, said detachably mounted means being used to impart said rotational movement to said disc member.

References Cited UNITED STATES PATENTS 2,264,075 11/1941 Frank 33922 2,281,221 4/1942 Anderson 339-22 X 2,369,860 2/1945 Schroeder 339- 2,786,908 3/1957 Constantine et a1. 200-50 3,028,460 4/1962 Turton 20051 3,122,603 2/ 1964 Atkinson 339-22 3,209,301 9/1965 Duffy 339-22 RICHARD E. MOORE, Primary Examiner PATRICK A. CLIFFORD, Assistant Examiner US or. X.R. 337 75; 200 41 

